Different types of moveable barrier operators have been sold over the years and these barrier operator systems have been used to actuate various types of moveable barriers. For example, garage door operators have been used to move garage doors and gate operators have been used to open and close gates.
In many such systems, multiple barriers are used. For example, in some gated entry systems, dual gates are employed. When the gates are in a fully closed position, a gap exists between the gates and some approach must be used to secure the gates together to prevent the gates from being opened and thereby prevent unauthorized entry into the area protected by the gates.
In some dual gates systems, a loose chain and padlock are used to secure the two gates together after closure. However, to avoid the inconvenience of using a chain and padlock, other dual gate systems use an overlapping section that surmounts the gap between the gates when the gates are fully closed. This overlapping portion may itself provide locking functionality (e.g., the overlapping section may be a magnetic lock, a solenoid lock, or some similar lock or locking arrangement) to secure the gates together. When gates include an overlapping portion, the gates have to be opened or closed in a specific order to prevent interference or collisions between the gates when the gates are moved.
Some previous systems utilizing overlapping sections have attempted to prevent gate collisions by using a delay feature. More specifically, a control element is used to delay the activation and movement of one of the gates by a set time period in order to prevent collisions between gates. Unfortunately, the speed that gates actually move often depends upon environmental conditions. For instance, if a gate is being propelled (or moving against) a high wind, the gate might move faster (or slower) than expected. Consequently, the delay adjustment approach often proves inadequate in preventing collisions.
Another problem associated with the above-mentioned delay-based approaches is that the delays selected are typically significant amounts of time in order to overcome the potential speed variation and therefore significantly increases the amount of time required to open and close gates. User frustration is created under such circumstances as users may be forced to wait for a gate's movement to be completed. Yet another problem with these previous approaches is that manual adjustments to the delay can only be made by an installer, creating the risk of misadjustments by this installer. In addition, the need to schedule maintenance adjustments by a trained installer creates inconvenience for the gate owner since they are often forced to be present when the adjustments are made. Also, when the installer arrives the environmental conditions that created a need for an adjustment may have changed. For instance, these changed conditions may alter the nature of or entirely remove the problem that necessitated the need for an adjustment. As a result, the adjustments made by the installer may become inadequate and/or be merely a guess.